Added first implementation of the evPlane wagon for the event plane...

DO NOT REMOVE THIS BOXED MESSAGE

Code in this merge request is subject to review by Code Owners.
The list of reviewers is posted in the comments section.
After all of the code is approved, please put a brief notice about it at the beginning of this message.

NOTE: Merging this code without getting it approved by Code Owners will result in suspending your developer rights!!!

Added first implementation of the evPlane wagon for the event plane measurements using FHCal and TPC. Recentering and shift EP corrections are implemented as well.

Main changes:
- Added wagon mpdroot/physics/evPlane/. Main classes and macros are inside this directory. General style and layout is similar to the other wagons.
- Added mpdroot/physics/MpdAnalysisEventPlane.[h,cxx]: simple class to store event plane angles in the MpdAnalysisEvent.
- Changes in mpdroot/physics/MpdAnalysisEvent.h: added field MpdAnalysisEventPlane fMpdEP to store event plane angles.